There is a member here who offers a grooming video. I don't have it myself but I have heard fantastic things about it. Here is a link to her sales thread - note that it was started in April of '08 so you might want to double check with her before ordering:
http://www.yorkietalk.com/forums/yor...ml#post2442218
As far as clippers go, buy the best set you can afford and take good care of them. NEVER EVER clip a dirty dog, it will dull your blades quicker than anything. I found this out the hard way with a $275 set of cordless Andis clippers we used on the horses. After several years of very heavy use the clipers finally wore out - I am going to have to bite the bullet and order another set of Anids - I will get the smaller cordless set for small animals.